Superstar Road is the ninth and final World of New Super Mario Bros. U and New Super Luigi U. There are a total of nine levels in this World. The first eight levels must be unlocked by collecting all of the Star Coins in the previous eight Worlds. To obtain the ninth and final level, you must complete the first eight levels in the Superstar Road, as well as obtain all of the Star Coins. This is the only World where the Propeller Mushroom and Penguin Suit, originally from New Super Mario Bros. Wii, makes a return.